I don't mind speed runs, it's just when, as people say, people force others to do it or complain to others about how they're doing it. As a healer I'm often shoved into speed runs without any sort of warning, the tank just runs off ahead and pulls a huge pack, which I don't mind, but I imagine it's daunting for new DPS who are like, 'What on earth is he doing?', then having the tank complain that the DPS can't get the huge pack down quick enough. Or rage quit. Or if it's a new tank in the group and the DPS or Healer wants the tank to speed run it when he's used to it and start trying to kick him for going too slow. That sucks as well.

If everyone is on the same page and wants to do the speed run, then that's fine, but if they're not, then it's not fine.